After leaving the conches such masses must be cooled and conditioned to bring them to the best possible state for further processing. For this purpose use is made of conditioning machines comprising a stack of cooling stages forming a cylinder and each having cooled top and bottom walls connected to a coolant recirculating system, and a pump forcing the mass through all the stages of which each contains scrapers revolving about the cylinder axis. The defect of such machines is their relatively poor throughput and the long time of cooling needed for conditioning the chocolate mass.